17 year old DS staying out every night

[Scarab]

My DS has been staying out till 3 and 4 in the morning most nights over the holiday. One of his friends has passed his driving test and has a car with unlimited petrol and my DS says they go cruising. I believe that there may be drugs involved. He has never been an easy child and we have struggled to get him to do any schoolwork. He attended a very good school, is reasonably bright and managed a decent haul of GCSEs but has recently failed his AS levels at sixth form college. He is surly and very difficult to talk to. He is going back to college to do Year 12 again on a different course and has said he will work this time but I fear otherwise. He thinks I am worrying too much and that I'm a control freak. I have had difficulty sleeping recently as I wait for him to get back in the night. My DH is also very worried about his future but cannot really understand the level of my concern. My friends' children do not behave like this. We cannot physically prevent him from going out but I would welcome some ideas for encouraging him to change his ways......

what else was there for him to do in the holidays? Why didn't he have a job, are you funding his lifestyle? Cut off his money unless he works and start showing him job ads.

He has applied for lots of jobs but nothing doing. He would like a job and we really have tried.

then he should be doing voluntary work/work experience or studying or engaging in some regular physical activity. My granny was right about the devil making work for idle hands. I'd have sent him off to do a residential with disabled people or something similar.

Agree with ellisbell to a degree. If he hasn't a job but you are keeping him he needs to be doing something "job like" not just dossing about with his mates- for instance I keep my kids financially because it is their "job" to study and they are doing it OK.
Voluntary work will enhance his CV and employability no end as will even a job flipping burgers in McDonalds for a few hours a week. If not then he gets up and helps at home/does jobs around the house/garden etc- he could even start with sorting his room out and repainting it as project...You can't prevent him but you can cut of his source of ready cash....